UC San Diego

Orthographic precision refers to the specificity with which letters are assigned to positions within words. In some theoretical models of visual word processing, precision is the optimal end state of a lexical representation; the associations between letters and positions are initially approximate and noisy, but they become more precise as readers gain exposure to the word. In other models, flexible orthographic codes that allow for rapid access to semantics are the optimal end state, and precise representations are only relied upon under specific circumstances. I will introduce a series of event-related potential transposed-letter priming studies designed to test the predictions of these opposing models and determine the functionality of precision within the orthographic system. More specifically, I examine the lexical properties that modulate precision within readers and the skills that modulate precision across readers. In Chapter 2, I demonstrate that words from high-density orthographic neighborhoods that are easy to confuse are encoded more precisely than words from low-density orthographic neighborhoods. In Chapter 3, I demonstrate that precision differs across languages in two groups of bilinguals with different levels of proficiency. In Chapter 4, I compare orthographic precision across hearing and deaf readers to examine how access to phonology contributes to orthographic tuning. However, the results indicate that there were negligible differences between groups. Overall, the results are consistent with a dynamic orthographic system in which precision varies systematically but does not necessarily characterize more developed representations.